One day⁠—some ten or twelve had passed since Hans Castorp retired to bed⁠—there was a knock on his door at about this hour, before Joachim had returned from dinner and the social half-hour. Upon Hans Castorp’s inquiring “Come in,” it opened, and Ludovico Settembrini appeared⁠—and lo, on the instant the room was flooded with light. For the visitor’s first motion, while still on the threshold, had been to turn on the electric light, which filled the room in a trice with vibrating brilliance, and reverberated from the gleaming white ceiling and furniture.